Shinichi Kobara

Geomorphometric Patterns of Nassau Grouper (Epinephelus striatus) Spawning Aggregation Sites in the Cayman Islands

Reef fish spawning aggregation sites are essential life habitats vulnerable to exploitation by fishermen, yet no quantitative comparisons of sites exist to understand their geomorphologic patterns. The objective of this study was to evaluate the geospatial aspects of known Nassau grouper spawning aggregation sites in the Cayman Islands. The results illustrate that the five known Nassau grouper spawning aggregation sites are located at convex-shaped reefs within 1 km of reef promontory tips. Further, all sites are found in 25–45 m depth, less than 50 m from shelf edges. Finally, they have been documented as multi-species spawning aggregation sites.

Geomorphology of Reef Fish Spawning Aggregations in Belize and the Cayman Islands (Caribbean)

Publisher Summary Caye Glory and Gladden Spit in Belize, and Grand Cayman East (GCE) and Little Cayman West (LCW) in the Cayman Islands, have a common geomorphologic signature and all harbor important breeding grounds for commercially important reef fishes. Most commercially important reef fishes, including many species of grouper and snapper, travel relatively long distances over the course of days or weeks to aggregate and spawn at very specific times and in very specific places. Locations of known sites were compiled using published literature and new field surveys and indicate commonality in the underlying geomorphology and species seasonality of reef fish spawning aggregation (FSA) sites throughout the wider Caribbean. Commercially important reef fish such as grouper and snapper use specific geomorphologic locations as spawning grounds throughout the wider Caribbean. In the Cayman Islands and Belize, fish choose shelf-edge reef promontories for spawning, and share these areas with other species. These multispecies spawning aggregation sites are generally located near the inflection points of convex-shaped reefs, in 20–40 m water depth, adjacent to sharp shelf edges where water depth drops to several hundred meters. Reef geomorphology may be the key determinant for the selection of reef fish breeding habitat. This chapter presents the three-dimensional structure of four representative spawning aggregation sites in the Cayman Islands and Belize.

Prediction and verification of possible reef‐fish spawning aggregation sites in Los Roques Archipelago National Park, Venezuela

This study attempts to predict and verify possible spawning aggregation sites and times in the Los Roques Archipelago National Park, Venezuela, based on physical reef characteristics and the knowledge of experienced local fishermen. Three possible aggregation sites were selected for monitoring based on satellite images, low-cost bathymetric mapping and interviews with experienced local fishermen. Abundances and sizes of 18 species that are known to form reproductive aggregations were monitored at these sites using underwater visual census for 7 days after each full moon from February to August, 2007. While spawning events were not observed, possible indirect evidence of spawning aggregations was found for Lutjanus analis at Cayo Sal and Boca de Sebastopol, Lutjanus apodus at Cayo Sal, Lutjanus cyanopterus at Cayo Sal and Piedra La Guasa and Epinephelus guttatus at Bajo California and Cayo de Agua. Additionally, indirect evidence was identified for the past existence of a spawning aggregation of Epinephelus striatus in the northern part of the archipelago, which may have been eliminated by overfishing c.15 years ago. Bathymetric mapping showed that the shelf edge at sites monitored in this study was shallower than at spawning aggregation sites in other parts of the Caribbean, and that sites were not proximal to deep water. While this study does not prove the existence or locations of spawning aggregations of reef fishes in the archipelago, it does add insight to a growing understanding of generalities in the relationship between seafloor characteristics and the locations of transient reef-fish spawning aggregations in the Caribbean.

Timing and locations of reef fish spawning off the southeastern United States

Managed reef fish in the Atlantic Ocean of the southeastern United States (SEUS) support a multi-billion dollar industry. There is a broad interest in locating and protecting spawning fish from harvest, to enhance productivity and reduce the potential for overfishing. We assessed spatiotemporal cues for spawning for six species from four reef fish families, using data on individual spawning condition collected by over three decades of regional fishery-independent reef fish surveys, combined with a series of predictors derived from bathymetric features. We quantified the size of spawning areas used by reef fish across many years and identified several multispecies spawning locations. We quantitatively identified cues for peak spawning and generated predictive maps for Gray Triggerfish (Balistes capriscus), White Grunt (Haemulon plumierii), Red Snapper (Lutjanus campechanus), Vermilion Snapper (Rhomboplites aurorubens), Black Sea Bass (Centropristis striata), and Scamp (Mycteroperca phenax). For example, Red Snapper peak spawning was predicted in 24.7–29.0°C water prior to the new moon at locations with high curvature in the 24–30 m depth range off northeast Florida during June and July. External validation using scientific and fishery-dependent data collections strongly supported the predictive utility of our models. We identified locations where reconfiguration or expansion of existing marine protected areas would protect spawning reef fish. We recommend increased sampling off southern Florida (south of 27° N), during winter months, and in high-relief, high current habitats to improve our understanding of timing and location of reef fish spawning off the southeastern United States.

One System, Many Societal Benefits: Building an Efficient, Cost-Effective Ocean Observing System for the Gulf of Mexico

Abstract During a decade of building the Gulf of Mexico Coastal Ocean Observing System (GCOOS), there has been convincing evidence that an integrated “system of systems” is an effective, efficient system that provides many societal benefits, including economic development opportunities. The Gulf community has come a long way toward establishing a regional ocean observing system, and with input from more than 700 stakeholders, the GCOOS Regional Association has developed a comprehensive blueprint for monitoring in the Gulf. This blueprint, the GCOOS Build-out Plan, can and should serve as a guide for future investments, including those intended to generate meaningful ecosystem indicators that inform the restoration process and ascertain the success of restoration efforts. With an unprecedented opportunity via The Clean Water Act penalty monies, the region is poised to build on extensive multi-institutional, interdisciplinary relationships to expand existing infrastructure into a comprehensive system that can address the myriad issues facing the Gulf.

Making sense of ocean sensing: the Gulf of Mexico Coastal Ocean Observing System links observations to applications

The Gulf of Mexico Coastal Ocean Observing System Regional Association (GCOOS-RA) works to enhance our ability to collect, deliver and use ocean information. The GCOOS-RA Education and Outreach Council works to bring together industry, governments, academia, formal and informal educators, and the public to assess regional needs for coastal ocean information, foster cooperation, and increase utility of the data. Examples of data products in varying stages of development are described, including web pages for recreational boaters and fishermen, novel visualizations of storm surge, public exhibits focused on five Gulf of Mexico Priority Issues defined by the Gulf of Mexico Alliance, a Harmful Algae Bloom warning system, the Basic Observation Buoy project designed to engage citizen scientists in ocean monitoring activities, and the GCOOS Data Portal, instrumental in Deepwater Horizon mitigation efforts.